U.S. patent number 9,163,894 [Application Number 13/284,195] was granted by the patent office on 2015-10-20 for laser transmission system for use with a firearm in a battle field training exercise.
This patent grant is currently assigned to Lockheed Martin Corporation. The grantee listed for this patent is Edward Steve Kaprocki, Kevin E. Keene, Steven Gordon Preston, Peter F. Reardon. Invention is credited to Edward Steve Kaprocki, Kevin E. Keene, Steven Gordon Preston, Peter F. Reardon.
United States Patent |
9,163,894 |
Reardon , et al. |
October 20, 2015 |
Laser transmission system for use with a firearm in a battle field
training exercise
Abstract
Laser transmission systems mountable on firearms are disclosed
along with methods of operating and configuring the same. The laser
transmissions systems are configured to detect that a sequence of
real-time mechanical vibrations on the firearm are in accordance
with a predetermined characteristic firing signature of the
firearm. In response, the laser transmission system initiates
transmission of a laser to simulate a munitions strike. The
predetermined characteristic firing signature is based on a
sequence of predetermined mechanical vibrations resulting from a
first pre-flash firing event and a subsequent second pre-flash
firing event. In this manner, the laser transmission system
initiates transmission of the laser prior to a flash event and more
accurately approximates a bullet trajectory.
Inventors: |
Reardon; Peter F. (Orlando,
FL), Preston; Steven Gordon (Winter Springs, FL),
Kaprocki; Edward Steve (Debary, FL), Keene; Kevin E.
(Orlando, FL) |
Applicant: |
Name |
City |
State |
Country |
Type |
Reardon; Peter F.
Preston; Steven Gordon
Kaprocki; Edward Steve
Keene; Kevin E. |
Orlando
Winter Springs
Debary
Orlando |
FL
FL
FL
FL |
US
US
US
US |
|
|
Assignee: |
Lockheed Martin Corporation
(Bethesda, MD)
|
Family
ID: |
54290300 |
Appl.
No.: |
13/284,195 |
Filed: |
October 28, 2011 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F41G
3/2655 (20130101); F41A 33/02 (20130101); F41A
33/00 (20130101); F41G 3/26 (20130101); F41A
19/01 (20130101); A63F 9/02 (20130101) |
Current International
Class: |
F41G
3/26 (20060101); F41A 33/00 (20060101); F41A
33/02 (20060101); A63F 9/02 (20060101) |
Field of
Search: |
;434/19,21 ;273/393
;345/173 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Unknown, "M240B Machine Gun Operators Course," Jun. 2011, 120
pages. cited by applicant .
Unknown, "M240 7.62mm Armor Machine Gun," 5 pages, accessed Jun.
14, 2011, http://inetres.com/gp/military/cv/weapon/M240.html. cited
by applicant.
|
Primary Examiner: Utama; Robert J
Attorney, Agent or Firm: Withrow & Terranova, PLLC
Claims
What is claimed is:
1. A laser transmission system mountable on a firearm, comprising:
a laser transmitter operable to transmit a laser; a sensing
apparatus operable to sense a sequence of real-time mechanical
vibrations of the firearm; a controller operably associated with
the laser transmitter and the sensing apparatus, the controller
being configured to: detect that the sequence of real-time
mechanical vibrations is in accordance with a predetermined
characteristic firing signature of the firearm wherein the
predetermined characteristic firing signature is based on a
sequence of predetermined mechanical vibrations that result from a
first pre-flash firing event and a subsequent second pre-flash
firing event, which are each associated with a firing of a munition
from the firearm; generate a laser initiation signal upon detecting
that the sequence of real-time mechanical vibrations is in
accordance with the predetermined characteristic firing signature
of the firearm, the laser initiation signal being operable to cause
the laser transmitter to initiate transmission of the laser; and in
response to detecting that the sequence of real-time mechanical
vibrations is in accordance with the predetermined characteristic
firing signature of the firearm, initiate transmission of the laser
by sending the laser initiation signal to the laser
transmitter.
2. The laser transmission system of claim 1 wherein the first
pre-flash firing event comprises a trigger pull action that
actuates a trigger of the firearm.
3. The laser transmission system of claim 2 wherein the subsequent
second pre-flash firing event comprises one of either a chambering
action that places the munition within a chamber of the firearm or
a munition discharge action.
4. The laser transmission system of claim 1 wherein the subsequent
second pre-flash firing event comprises one of either a chambering
action that places the munition within a chamber of the firearm or
a munition discharge action.
5. The laser transmission system of claim 1 wherein the munition
comprises a blank munition, the firearm comprises an open-bolt
machine gun, and the first pre-flash firing event and the
subsequent second pre-flash firing event are each associated with
the firing of the blank munition from the open-bolt machine
gun.
6. The laser transmission system of claim 5, wherein: the laser
transmitter is operable to transmit the laser such that the laser
comprises kill messages that are formatted in accordance with a
Multiple Integrated Laser Engagement System (MILES), wherein MILES
requires an adequate number of kill messages to be received from
the laser transmitter for a laser receiver to register a kill; the
first pre-flash firing event comprises a trigger pull action that
actuates a trigger of the open-bolt machine gun; and the subsequent
second pre-flash firing event is sufficiently prior to a flash
event in which a flash of the blank munition exits a barrel of the
open-bolt machine gun such that initiating transmission of the
laser by the laser transmitter provides sufficient time for the
laser transmitter to transmit the adequate number of kill messages
in the laser before the flash event.
7. The laser transmission system of claim 5, wherein after
detecting that the sequence of real-time mechanical vibrations are
in accordance with the predetermined characteristic firing
signature and prior to a trigger return action: the sensing
apparatus is operable to sense a second sequence of real-time
mechanical vibrations of the open-bolt machine gun; the controller
is configured to: detect that the second sequence of real-time
mechanical vibrations are in accordance with a second predetermined
characteristic firing signature of the open-bolt machine gun
wherein the second predetermined characteristic firing signature is
based on a second sequence of predetermined mechanical vibrations
that result from a flash event and a third pre-flash firing event
prior to a second flash event in which a flash of a subsequent
blank munition exits a barrel of the firearm; and in response to
detecting that the second sequence of real-time mechanical
vibrations are in accordance with the second predetermined
characteristic firing signature of the open-bolt machine gun,
again, initiating transmission of the laser by the laser
transmitter.
8. The laser transmission system of claim 1, wherein: the sensing
apparatus is operable to sense the sequence of real-time mechanical
vibrations of the firearm by generating a sequence of real-time
electronic responses based on the sequence of real-time mechanical
vibrations of the firearm; and the predetermined characteristic
firing signature comprises a sequence of predetermined electronic
responses based on the sequence of predetermined mechanical
vibrations.
9. The laser transmission system of claim 8, wherein the controller
is configured to detect that the sequence of real-time mechanical
vibrations are in accordance with the predetermined characteristic
firing signature of the firearm by detecting a first one of the
sequence of real-time electronic responses at least as high as a
first minimum amplitude level and, in response to detecting the
first one of the sequence of real-time electronic responses,
detecting a second one of the sequence of real-time electronic
responses at least as high as a second minimum amplitude level and
within a time period after the first one of the sequence of
real-time electronic responses and wherein: the first minimum
amplitude level is based on the sequence of predetermined
electronic responses that correspond to the sequence of
predetermined mechanical vibrations resulting from the first
pre-flash firing event; the second minimum amplitude level is based
on the sequence of predetermined electronic responses that
correspond to the sequence of predetermined mechanical vibrations
resulting from the subsequent second pre-flash firing event; and
the time period is based on a temporal distance between the
sequence of predetermined electronic responses that correspond to
the sequence of predetermined mechanical vibrations resulting from
the first pre-flash firing event and the sequence of predetermined
electronic responses that correspond to the sequence of
predetermined mechanical vibrations resulting from the subsequent
second pre-flash firing event.
10. The laser transmission system of claim 9, wherein: the first
pre-flash firing event comprises a trigger pull action that
actuates a trigger of the firearm; and the subsequent second
pre-flash firing event comprises one of either a chambering action
that places the munition within a chamber of the firearm and a
munition discharge action that discharges the munition, whereby the
second minimum amplitude level is higher than the first minimum
amplitude level.
11. The laser transmission system of claim 1, wherein the
controller is configured to detect that the sequence of real-time
mechanical vibrations are in accordance with the predetermined
characteristic firing signature of the firearm by: detecting that
at least a first real-time mechanical vibration from the sequence
of real-time mechanical vibrations is in accordance with a first
pre-flash characteristic firing event signature in the
predetermined characteristic firing signature, the first pre-flash
characteristic firing event signature corresponding to the sequence
of predetermined mechanical vibrations that result from the first
pre-flash firing event; and detecting that at least a second
real-time mechanical vibration from the sequence of real-time
mechanical vibrations is in accordance with a second pre-flash
characteristic firing event signature in the predetermined
characteristic firing signature, the second pre-flash
characteristic firing event signature corresponding to the sequence
of predetermined mechanical vibrations that result from the
subsequent second pre-flash firing event.
12. The laser transmission system of claim 11, wherein: the first
pre-flash characteristic firing event signature is associated with
a first vibrational level; the second pre-flash characteristic
firing event signature is associated with a second vibrational
level, the second vibrational level higher than the first
vibrational level; the sensing apparatus comprising a piezoelectric
sensor; the controller is operable to adjust a vibrational
sensitivity of the piezoelectric sensor to set a minimum
vibrational level detectable by the controller; wherein the
controller is configured to detect that the at least the first
real-time mechanical vibration from the sequence of real-time
mechanical vibrations is in accordance with the first pre-flash
firing event by setting the minimum vibrational level to the first
vibrational level and the controller is configured to detect that
the at least the second real-time mechanical vibration is in
accordance with the second pre-flash characteristic firing event
signature by setting the minimum vibrational level to the second
vibrational level.
13. The laser transmission system of claim 12, wherein the
controller is further configured to detect that the at least the
second real-time mechanical vibration is in accordance with the
second pre-flash characteristic firing event signature by
determining that the at least the second real-time mechanical
vibration occurs during a time period after the at least the first
real-time mechanical vibration based on a temporal distance between
the first pre-flash characteristic firing event signature and the
second pre-flash characteristic firing event signature in the
predetermined characteristic firing signature.
14. A method of initiating transmission of a laser from a laser
transmitter mounted on a firearm, comprising: sensing a sequence of
real-time mechanical vibrations of the firearm; detecting that the
sequence of real-time mechanical vibrations is in accordance with a
predetermined characteristic firing signature of the firearm
wherein the predetermined characteristic firing signature is based
on a sequence of predetermined mechanical vibrations that result
from a first pre-flash firing event and a subsequent second
pre-flash firing event, which are each associated with a firing of
a munition from the firearm; generating a laser initiation signal
upon detecting that the sequence of real-time mechanical vibrations
is in accordance with the predetermined characteristic firing
signature of the firearm, the laser initiation signal being
operable to cause the laser transmitter to initiate transmission of
the laser; and initiating the transmission of the laser by sending
the laser initiation signal to the laser transmitter in response to
the detecting that the sequence of real-time mechanical vibrations
is in accordance with the predetermined characteristic firing
signature of the firearm.
15. The method of claim 14 wherein the first pre-flash firing event
comprises a trigger pull action that actuates a trigger of the
firearm.
16. The method of claim 15 wherein the subsequent second pre-flash
firing event comprises one of either a chambering action that
places the munition within a chamber of the firearm or a munition
discharge action that discharges the munition.
17. A laser transmission system mountable on a firearm, comprising:
a laser transmitter operable to transmit a laser; one or more
accelerometers wherein the one or more accelerometers are operable
to sense a sequence of real-time mechanical vibrations on the
firearm along a first three orthogonal directions; and an analog
controller operably associated with the one or more accelerometers
and being configured to provide a transfer function, wherein the
transfer function is provided such that the analog controller
initiates transmission of the laser when the sequence of real-time
mechanical vibrations is in accordance with a predetermined
characteristic firing signature that is based on a sequence of
predetermined mechanical vibrations along a second three orthogonal
directions.
18. The laser transmission system of claim 17, wherein the first
three orthogonal directions and the second three orthogonal
directions are substantially the same.
19. The laser transmission system of claim 17, wherein the sequence
of predetermined mechanical vibrations occur prior to a flash
event.
20. A laser transmission system mountable on an open-bolt machine
gun, comprising: a laser transmitter operable to transmit a laser;
a sensing apparatus operable to sense a sequence of real-time
mechanical vibrations of the open-bolt machine gun; a controller
operably associated with the laser transmitter and the sensing
apparatus, the controller being configured to: detect that the
sequence of real-time mechanical vibrations is in accordance with a
predetermined characteristic firing signature of the open-bolt
machine gun wherein the predetermined characteristic firing
signature is based on a sequence of predetermined mechanical
vibrations that result from a first pre-flash firing event and a
subsequent second pre-flash firing event, which are each associated
with a firing of a blank munition from the open-bolt machine gun,
the first pre-flash firing event comprising a trigger pull action
that actuates a trigger of the open-bolt machine gun; and in
response to detecting that the sequence of real-time mechanical
vibrations is in accordance with the predetermined characteristic
firing signature of the firearm, initiate transmission of the laser
by the laser transmitter, wherein the laser transmitter is operable
to transmit the laser such that the laser comprises kill messages
that are formatted in accordance with a Multiple Integrated Laser
Engagement System (MILES), wherein MILES requires an adequate
number of kill messages to be received from the laser transmitter
for a laser receiver to register a kill, the subsequent second
pre-flash firing event being sufficiently prior to a flash event in
which a flash of the blank munition exits a barrel of the open-bolt
machine gun such that initiating transmission of the laser by the
laser transmitter provides sufficient time for the laser
transmitter to transmit the adequate number of kill messages in the
laser before the flash event.
21. A laser transmission system mountable on an open-bolt machine
gun, comprising: a laser transmitter operable to transmit a laser;
a sensing apparatus operable to sense a first sequence of real-time
mechanical vibrations of the open-bolt machine gun and a second
sequence of real-time mechanical vibrations of the open-bolt
machine gun; and a controller operably associated with the laser
transmitter and the sensing apparatus, the controller being
configured to: detect that the first sequence of real-time
mechanical vibrations is in accordance with a first predetermined
characteristic firing signature of the open-bolt machine gun
wherein the first predetermined characteristic firing signature is
based on a first sequence of predetermined mechanical vibrations
that result from a first pre-flash firing event and a subsequent
second pre-flash firing event, which are each associated with a
firing of a blank munition from the open-bolt machine gun; and in
response to detecting that the first sequence of real-time
mechanical vibrations is in accordance with the first predetermined
characteristic firing signature of the open-bolt machine gun,
initiate transmission of the laser by the laser transmitter; detect
that the second sequence of real-time mechanical vibrations is in
accordance with a second predetermined characteristic firing
signature of the open-bolt machine gun wherein the second
predetermined characteristic firing signature is based on a second
sequence of predetermined mechanical vibrations that result from a
flash event and a third pre-flash firing event prior to a second
flash event in which a flash of a subsequent blank munition exits a
barrel of the firearm; and in response to detecting that the second
sequence of real-time mechanical vibrations is in accordance with
the second predetermined characteristic firing signature of the
open-bolt machine gun, again, initiating transmission of the laser
by the laser transmitter.
22. A laser transmission system mountable on a firearm, comprising:
a laser transmitter operable to transmit a laser; a sensing
apparatus operable to sense a sequence of real-time mechanical
vibrations of the firearm by generating a sequence of real-time
electronic responses based on the sequence of real-time mechanical
vibrations of the firearm; and a controller operably associated
with the laser transmitter and the sensing apparatus, the
controller being configured to: detect that the sequence of
real-time mechanical vibrations is in accordance with a
predetermined characteristic firing signature of the firearm
wherein the predetermined characteristic firing signature comprises
a sequence of predetermined electronic responses based on a
sequence of predetermined mechanical vibrations that result from a
first pre-flash firing event and a subsequent second pre-flash
firing event, which are each associated with a firing of a munition
from the firearm; and in response to detecting that the sequence of
real-time mechanical vibrations is in accordance with the
predetermined characteristic firing signature of the firearm,
initiate transmission of the laser by the laser transmitter.
23. A laser transmission system mountable on a firearm, comprising:
a laser transmitter operable to transmit a laser; a sensing
apparatus operable to sense a sequence of real-time mechanical
vibrations of the firearm; and a controller operably associated
with the laser transmitter and the sensing apparatus, the
controller being configured to: detect that the sequence of
real-time mechanical vibrations is in accordance with a
predetermined characteristic firing signature of the firearm
wherein the predetermined characteristic firing signature is based
on a sequence of predetermined mechanical vibrations that result
from a first pre-flash firing event and a subsequent second
pre-flash firing event, which are each associated with a firing of
a munition from the firearm, wherein the controller is configured
to detect that the sequence of real-time mechanical vibrations are
in accordance with the predetermined characteristic firing
signature of the firearm by: detecting that at least a first
real-time mechanical vibration from the sequence of real-time
mechanical vibrations is in accordance with a first pre-flash
characteristic firing event signature in the predetermined
characteristic firing signature, the first pre-flash characteristic
firing event signature corresponding to the sequence of
predetermined mechanical vibrations that result from the first
pre-flash firing event; and detecting that at least a second
real-time mechanical vibration from the sequence of real-time
mechanical vibrations is in accordance with a second pre-flash
characteristic firing event signature in the predetermined
characteristic firing signature, the second pre-flash
characteristic firing event signature corresponding to the sequence
of predetermined mechanical vibrations that result from the
subsequent second pre-flash firing event; and in response to
detecting that the sequence of real-time mechanical vibrations is
in accordance with the predetermined characteristic firing
signature of the firearm, initiate transmission of the laser by the
laser transmitter.
24. A method of initiating transmission of a laser from a laser
transmitter mounted on a firearm, comprising: sensing a sequence of
real-time mechanical vibrations of the firearm by generating a
sequence of real-time electronic responses based on the sequence of
real-time mechanical vibrations of the firearm; detecting that the
sequence of real-time mechanical vibrations is in accordance with a
predetermined characteristic firing signature of the firearm
wherein the predetermined characteristic firing signature comprises
a sequence of predetermined electronic responses based on a
sequence of predetermined mechanical vibrations that result from a
first pre-flash firing event and a subsequent second pre-flash
firing event, which are each associated with a firing of a munition
from the firearm; and initiating the transmission of the laser by
the laser transmitter in response to the detecting that the
sequence of real-time mechanical vibrations is in accordance with
the predetermined characteristic firing signature of the
firearm.
25. A method of initiating transmission of a laser from a laser
transmitter mounted on a firearm, comprising: sensing a sequence of
real-time mechanical vibrations of the firearm; detecting that the
sequence of real-time mechanical vibrations is in accordance with a
predetermined characteristic firing signature of the firearm
wherein the predetermined characteristic firing signature is based
on a sequence of predetermined mechanical vibrations that result
from a first pre-flash firing event and a subsequent second
pre-flash firing event, which are each associated with a firing of
a munition from the firearm, wherein detecting that the sequence of
real-time mechanical vibrations are in accordance with the
predetermined characteristic firing signature of the firearm
includes: detecting that at least a first real-time mechanical
vibration from the sequence of real-time mechanical vibrations is
in accordance with a first pre-flash characteristic firing event
signature in the predetermined characteristic firing signature, the
first pre-flash characteristic firing event signature corresponding
to the sequence of predetermined mechanical vibrations that result
from the first pre-flash firing event; and detecting that at least
a second real-time mechanical vibration from the sequence of
real-time mechanical vibrations is in accordance with a second
pre-flash characteristic firing event signature in the
predetermined characteristic firing signature, the second pre-flash
characteristic firing event signature corresponding to the sequence
of predetermined mechanical vibrations that result from the
subsequent second pre-flash firing event; and initiating the
transmission of the laser by the laser transmitter in response to
detecting that the sequence of real-time mechanical vibrations is
in accordance with the predetermined characteristic firing
signature of the firearm.
Description
FIELD OF THE DISCLOSURE
Embodiments disclosed herein relate generally to laser transmission
systems, and in particular to laser transmission systems for use
with a firearm in a battle field training exercise.
BACKGROUND
Militaries around the world use military combat training systems to
help train military personnel for battle. To more realistically
simulate battle conditions, military combat training systems have
been developed that allow for the military personnel to use actual
military equipment and weaponry during the battle field training
exercises. Firearms used by participants in such battle field
exercises may be mounted with laser transmission systems, and may
also be loaded with blank munitions to closely simulate actual
firing conditions. The laser transmission systems generate a laser
that travels along an approximated bullet trajectory. Participants
wear or otherwise carry a laser receiver system that registers a
"hit" when struck by a laser.
Some automatic weapons used in such exercises depend on high
pressures in the chamber generated by the combustion of the
propellant to cycle the firearm and chamber the next round. If a
blank munition is used, there is no bullet to seal the barrel, and
the combustion gases exit through the muzzle without building up
enough pressure to chamber the next round. In these circumstances a
blank fire adaptor (BFA) is used. A BFA fits on the end of the
barrel of a firearm and partially blocks the muzzle of the firearm,
thereby causing sufficient pressure in the chamber to cycle the
weapon and chamber the next round.
Some laser transmission systems initiate transmission of the laser
based on a detected vibration of the firearm, such as the vibration
associated with the discharge of the blank munition. Unfortunately,
this enables a participant to "cheat" by causing the laser
transmission system to initiate transmission of the laser by simply
striking the firearm with an object. Other laser transmission
systems initiate transmission of the laser using an acoustic sensor
to detect the actuation of the trigger. The sensitivity levels
needed to measure trigger actuation make these laser transmission
systems vulnerable to noise and still enable a participant to
cheat.
More recently, laser transmission systems have been developed that
initiate transmission of the laser by measuring both the mechanical
vibrations associated with a discharge of the munition and the
subsequent sound or flash at the muzzle of the firearm caused by
the discharge of the munition. Such subsequent sound or flash may
be referred to herein as a "flash event." Delaying transmission of
the laser until, or after, detection of the flash event greatly
reduces, or eliminates, cheating by a participant.
Unfortunately, especially when a BFA is used, the forces associated
with a flash event tend to cause the barrel of the firearm to skew,
or deviate, from the direction it is aimed. Consequently, a laser
transmission system used with a machine gun that includes a BFA,
and that relies upon detection of the flash event to initiate
transmission of the laser, necessarily initiates transmission of
the laser after a point in time that the barrel has begun to
deviate from the target due to the forces associated with the flash
event. This deviation also causes the laser to deviate from the
target, and may result in a "miss" rather than a "hit," even though
the firearm was properly and accurately aimed at the target when
the trigger was pulled. This sequence of events makes it difficult
to assess the aiming accuracy of the participant.
In an attempt to compensate for transmitting the laser after the
barrel has begun to deviate, manufacturers have increased laser
power to increase the diameter of the bloom of the laser to
increase the likelihood that the edge of the bloom will contact the
laser receiver system. However, the increased laser diameter only
partially compensates for the barrel deviation, and unfortunately
the increase in laser power causes such laser systems to not be
"eye-safe." Laser systems that are not eye-safe may not be
practical in many training exercises, or may require additional
protective material to be worn by participants, reducing the
realism of the exercise.
Accordingly, there is a need for a laser transmission system that
accurately approximates a bullet trajectory and prevents military
personnel from initiating transmission of the laser without
actually firing a munition.
SUMMARY
Those skilled in the art will appreciate the scope of the present
disclosure and realize additional aspects thereof after reading the
following detailed description of the preferred embodiments in
association with the accompanying drawing figures.
This disclosure relates generally to laser transmission systems
mountable on firearms for use in training exercises. The laser
transmission system reduces, or renders impossible, the ability for
a participant to initiate a laser transmission without actually
firing the firearm, by conditioning the initiation of the laser on
the detection of multiple predetermined sequences of vibrations
associated with the firing of a round of ammunition. The laser
transmission system maintains laser accuracy by ensuring that the
transmission is initiated prior to a flash event so that the laser
is transmitted in a direction that accurately represents how the
firearm was aimed at the time the trigger was pulled.
In one embodiment, the laser transmission system includes a laser
transmitter that transmits a laser to simulate a munitions strike
from the firearm. When a munition is fired from the firearm, a
sensing apparatus senses the sequence of real-time mechanical
vibrations associated with a fired munition. A controller is
operably associated with the sensing apparatus and configured to
detect, or otherwise determine, that the sequence of real-time
mechanical vibrations are in accordance with a predetermined
characteristic firing signature of the firearm, and thus that
firearm is actually being fired, and that the detected vibrations
are not the result of a blow to the firearm. In response to such
determination, the controller causes the laser transmitter to
initiate transmission of the laser.
In one embodiment, the predetermined characteristic firing
signature of the firearm is based on a sequence of predetermined
mechanical vibrations resulting from a first pre-flash firing event
and a subsequent second pre-flash firing event. Each pre-flash
firing event is associated with the firing of a munition from the
firearm and occurs prior to the flash event during the munition
firing cycle of the firearm. As a result, the controller initiates
transmission of the laser prior to the movements in firearm
orientation resulting from the flash event so that the laser more
accurately approximates a bullet trajectory. Furthermore, the
controller inhibits the ability of military personnel to cheat
because, to initiate transmission of the laser, the sequence of
real-time mechanical vibrations have to be in accordance with the
sequence of predetermined mechanical vibrations in the
predetermined characteristic firing signature resulting from at
least two pre-flash firing events associated with the firing of a
munition.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The accompanying drawing figures incorporated in and forming a part
of this specification illustrate several aspects of the disclosure,
and together with the description serve to explain the principles
of the disclosure.
FIG. 1 illustrates one embodiment of an M240 machine gun.
FIGS. 2A and 2B illustrate one embodiment of a firing mechanism,
feed tray, and a munitions belt for the M240 machine gun shown in
FIG. 1.
FIG. 3 illustrates one embodiment of a laser transmission system
and a blank fire adaptor mounted on a barrel of the M240 machine
gun shown in FIG. 1.
FIG. 4 illustrates a block diagram of the laser transmission system
shown in FIG. 3.
FIG. 5 illustrates exemplary procedures for designing a controller
in the laser transmission system shown in FIG. 4.
FIG. 6 illustrates one embodiment of a predetermined characteristic
firing signature for the M240 machine gun shown in FIG. 1.
FIG. 7 illustrates one embodiment of sequences of real-time
electronic responses resulting from sequences of real-time
electronic vibrations.
FIG. 8 illustrates one embodiment of a sensing apparatus for the
laser transmission system shown in FIG. 4.
FIG. 9 illustrates one embodiment of a controller shown in FIG.
4.
FIG. 10 illustrates exemplary procedures implemented by the laser
transmission system of FIG. 4 to initiate transmission of a
laser.
FIG. 11 illustrates one embodiment of a second predetermined
characteristic firing signature.
FIG. 12 illustrates another embodiment of a predetermined
characteristic firing signature for the M240 machine gun shown in
FIG. 1.
FIG. 13 illustrates another embodiment of the sensing apparatus of
the laser transmission system shown in FIG. 4.
FIG. 14 illustrates another embodiment of sequences of real-time
electronic responses resulting from sequences of real-time
electronic vibrations.
FIG. 15 illustrates another embodiment of the controller shown in
FIG. 4.
DETAILED DESCRIPTION
The embodiments set forth below represent the necessary information
to enable those skilled in the art to practice the embodiments and
illustrate the best mode of practicing the embodiments. Upon
reading the following description in light of the accompanying
drawing figures, those skilled in the art will understand the
concepts of the disclosure and will recognize applications of these
concepts not particularly addressed herein. It should be understood
that these concepts and applications fall within the scope of the
disclosure and the accompanying claims.
Military combat training systems allow actual military equipment
and weapons to be used by military personnel during a battle field
training exercise. This provides the military with a more realistic
training environment so that the battle performance of military
personnel can be more accurately determined. To simulate a battle,
military personnel and/or vehicles are provided with a laser
receiver system and weapons strikes are simulated by the
transmission of lasers. If the laser receiver system is illuminated
by one or more of these lasers, the laser receiver system
determines whether to register a "kill."
The embodiments disclosed herein relate generally to laser
transmission systems mountable on firearms and methods of operating
and configuring the same. Embodiments of the laser transmission
systems may be mounted on the firearm and transmit a laser to
simulate munition strikes when a munition, such as a blank
munition, is fired from the firearm. In this manner, the laser
receiver systems employed by the military combat training system
may be illuminated by the laser and determine whether to register a
"kill".
Embodiments of the laser transmission systems disclosed herein
initiate transmission of the laser prior to a flash event.
Accordingly, the laser more accurately simulates a munition strike
since the laser is initiated prior to the changes in orientation
resulting from the mechanical vibrations of the flash event. Thus,
unlike prior laser transmission systems, the gun operator's
inability to hit a target during a battle field training exercise
can no longer be blamed on the gun jump resulting from the flash
event. Therefore, the performance of military personnel can be more
accurately judged from the battle field training exercise. The
laser transmission systems and methods are particularly beneficial
for use with firearms, such as bolt-back machine guns, that
experience significant forces and mechanical vibrations during
flash events.
FIG. 1 illustrates one embodiment of a firearm 10 and a laser
transmission system 12 mounted on the firearm 10. In this
embodiment, the firearm 10 is a bolt-back machine gun and, in
particular, a M240 machine gun. The firearm 10 has a barrel 14,
receiver assembly 16, a feed assembly 18, a trigger 20, a trigger
housing assembly 22, and a butt stock 24. The receiver assembly 16
houses a firing mechanism that operates to discharge munitions
placed within a chamber of the firearm 10. The firing mechanism of
a bolt-back machine gun, such as the M240 machine gun, typically
includes a spring apparatus. To fire a munition from the firearm
10, bolt-back machine guns need to place the firing mechanism in a
fire ready position. Initially, a gun operator may place the firing
mechanism in a fire ready position by pulling the firing mechanism
toward the back of the firearm 10. This compresses the spring
apparatus and the firing mechanism is held in place by the trigger
20 or a mechanism associated with the trigger 20.
The trigger housing assembly 22 houses the trigger 20 and includes
a handle 22A that allows a gun operator to grip the firearm 10. To
begin firing munitions, the gun operator pulls the trigger 20. The
actuation of the trigger 20 releases the firing mechanism and the
firing mechanism is propelled forward by the energy from the
compressed spring apparatus. The firing mechanism then strikes the
munition within the chamber of the firearm to discharge the
munition. The butt stock 24 attaches to the receiver assembly 16
and helps the gun operator absorb the recoil from the firearm 10
caused by the discharge of the munition.
In gas-operated automatic machine guns, such as the M240 machine
gun, the gases propelled by the discharge of the munition are fed
back to force the firing mechanism back into the fire ready
position. The spring apparatus is thereby again compressed. During
automatic fire, the cycle is repeated as long as the trigger 20
remains depressed and munitions are available to be fired. In other
types of firearms 10, such as semi-automatic firearms, the trigger
20 may need to be pulled to fire each munition.
Munitions include a cartridge and a propellant, such as gun powder,
enclosed within the cartridge. Live munitions typically also
include a bullet, while blank munitions do not include a bullet.
When live munitions are fired by the firearm 10, the bullet is
propelled by the discharge of the munition through the barrel 14.
The trajectory followed by the bullet depends on the orientation of
the firearm 10 when the bullet is exiting the barrel 14. Typically,
blank munitions are fired from the firearm 10 during battle field
training exercises. The laser transmission system 12 may be mounted
on the firearm 10 to transmit a laser 26 along a transmission path
28A. The transmission path 28A may approximate a bullet trajectory
28B. In this embodiment, the laser transmission system 12 is
mounted on the barrel 14 of the firearm 10 and the laser 26 is
transmitted in a direction substantially parallel to the barrel 14
and a line of sight 27 of the firearm 10. However, alternative
embodiments of the laser transmission system 12 are mountable on
other parts of the firearm 10, such as for example, the receiver
assembly 16.
The transmission path 28A approximates the bullet trajectory 28B
but does not necessarily have to exactly follow the bullet
trajectory 28B to accurately simulate munition strikes from the
firearm 10. While the transmission path 28A is substantially
parallel to the barrel 14, the transmission path 28A and the bullet
trajectory 28B may not be substantially parallel since the laser 26
may be initiated and transmitted before and/or after a bullet would
be exiting the barrel 14. This may depend on the timing for
initiating and duration of laser transmission. Also, due to the
recoil of some firearms 10, the transmission path 28A may not be
static. Instead, the transmission path 28A may fluctuate due to the
mechanical vibrations that result from firing the munition.
Consequently, the transmission path 28A of laser 26 and the bullet
trajectory 28B may not be substantially parallel but rather cross
after a distance from the firearm 10. In fact, after great
distances the transmission path 28A and the bullet trajectory 28B
typically have to diverge since the laser 26 may follow a somewhat
linear path while the bullet trajectory 28B is hyperbolic since the
bullet eventually falls back to earth. Furthermore, even when the
transmission path 28A is maintained substantially parallel to the
bullet trajectory 28B, the transmission path 28A may not be coaxial
with the bullet trajectory 28B.
However, the transmission path 28A of the laser 26 does not have to
exactly follow, be substantially parallel to, or remain static
relative to the bullet trajectory 28B in order for the laser 26 to
accurately simulate a munition strike from the firearm 10. Rather,
the transmission path 28A approximates the bullet trajectory 28B so
long as a distance 30 from a normal 32 of the bullet trajectory 28B
is maintained within an acceptable error range in accordance with
the requirements of the military combat training system. What error
ranges are acceptable may depend on factors such as the accuracy
required by a particular type of military combat training system,
the firing specifications of the firearm 10, the design of the
military combat training system or the battle field training
exercises implemented using the military combat training system,
and/or the particular circumstances in which the firearm 10 may be
used in the particular battle field training exercise.
The transmission path 28A does not have to approximate the bullet
trajectory 28B the entire time that the laser 26 is being
transmitted from the laser transmission system 12 to accurately
simulate a munitions strike. Rather, the transmission path 28A
simply needs to approximate the bullet trajectory 28B long enough
for a laser receiver system to register a "kill." The laser
transmission system 12 initiates transmission of the laser 26 prior
to a flash event to help ensure that the munition strikes from the
firearm accurately reflect the bullet trajectory 28B long enough to
register a "kill."
Referring now to FIGS. 1, 2A, and 2B, FIGS. 2A and 2B illustrate
one embodiment of a firing mechanism 34 of the firearm 10 and
portions of the feed assembly 18 (shown in FIG. 1). The M240
machine gun is fed from a belt 36 of munitions 38. Each munition 38
is a blank munition and has been placed in a link 40 of the belt
36. Other embodiments of the firearm 10 may be fed from clips,
magazines, and the like. The feed assembly 18 has a feed tray 42
and a cover assembly 44 (shown in FIG. 1). Both the feed tray 42
and the cover assembly 44 are movably attached to the receiver
assembly 16 (shown in FIG. 1) To load the firearm 10, the gun
operator first lowers the feed tray 42 onto the receiver assembly
16 and places the first munition 38A in the belt 36 within a tray
groove 46 formed in the feed tray 42. The remainder of the belt 36
is then laid across the feed tray 42 and then the cover assembly 44
of the feed mechanism is lowered onto the feed tray 42.
The firing mechanism 34 is housed within the receiver assembly 16
(FIG. 1) and includes a bolt/operating rod assembly 48 and a spring
rod 50 receivable by the bolt/operating rod assembly 48. The
bolt/operating rod assembly 48 includes a bolt 48A and an operating
rod 48B movably connected to one another. In this example, the M240
machine gun (FIG. 1) is a bolt-back machine gun. After the M240
machine gun has been loaded, the gun operator may pull a cocking
handle (not shown) to position the firing mechanism 34 toward a
back end 52 (FIG. 1) of the receiver assembly 16. In this manner,
the spring rod 50 is compressed and the firing mechanism 34 is
placed in a fire ready position. The bolt/operating rod assembly 48
may have a sear and the trigger 20 that forms a sear notch. To hold
the firing mechanism 34 in the fire ready position, the sear of the
bolt/operating rod assembly 48 inserts into the sear notch of the
trigger 20. The bolt-back machine gun is ready to be fired.
The gun operator may now begin firing munitions 38 from the firearm
10. The firearm 10 accomplishes the firing of munitions 38 via a
sequence of firing actions. A firing action is any action that is
performed by the various components of the firearm 10 during a
munitions firing cycle. Exemplary firing actions of the M240
machine gun are listed below. Note however that the firing actions
do not necessarily occur in a mutually exclusive sequence but may
partially overlap one another.
1. Trigger pull action. The trigger pull action is the actuation of
the trigger 20. Generally, the trigger pull action is caused when
the gun operator pulls the trigger 20. For the M240 machine gun,
actuating the trigger 20 releases the sear in the bolt/operating
rod assembly 48 from the sear notch in the trigger 20. This allows
the bolt/operating rod assembly 48 to be driven forward by the
force of the spring rod 50.
2. Munition Stripping Action. The munition stripping action strips
a munition 38 from the belt 36 and pushes a link 40 in the belt 36
out the side of the firearm 10. In the M240 machine gun, feed pawls
within the cover assembly 44 position the munition 38. The bolt 48A
then engages the munition 38. The forward movement of the
bolt/operating rod assembly 48 strips the munition 38 from the belt
36 and pushes the link 40 of a fired round out the side of the M240
machine gun.
3. Chambering Action. The chambering action places the munition 38
within a chamber of the firearm 10. In the M240 machine gun, the
bolt 48A continues to engage the munition 38 and a chambering ramp
in the feed tray 42 guides with munition 38 into the chamber as the
bolt/operating rod assembly 48 continue to be propelled
forward.
4. Locking Action. The locking action stops the forward movement of
the bolt 48A while allowing the operating rod 48B to continue
moving forward. The bolt 48A is stopped in the M240 machine gun
when a locking lever on the bolt 48A is placed within a breech
formed by the barrel 14. The barrel 14 and the breech of the M240
machine gun do not actually interlock but rather the locking lever
is simply placed in the breech to stop the movement of the bolt
48A.
5. Munition Discharge Action. A munition discharge action
discharges the munition 38 within the chamber of the firearm 10.
With regards to the M240 machine gun, a firing pin is provided
within the bolt 48A. While the bolt 48A has been stopped by the
breech in the barrel 14, the firing pin is driven forward by the
operating rod 48B and strikes the munition 38. This ignites the gun
powder within the munition 38 to discharge the munition 38.
6. Unlocking Action. To complete the munition firing cycle, the
firing mechanism 34 needs to be placed back into the fire ready
position. This begins when the unlocking action frees the bolt 48A
so that the bolt 48A may move rearward. For the M240 machine gun,
gases propelled by the discharge munition 38 are fed back from a
gas plug regulator in the barrel 14 to a gas cylinder that drives a
gas propelled piston. The rapidly expanding gases drive the gas
piston to force the bolt/operating rod assembly 48 to the rear.
During the primary movement, the operating rod 48B moves
independently of the bolt 48A for a short distance. At this point,
the locking lever begins to swing toward the rear, carrying the
bolt 48A with it into its unlocked position, and clearing the
breech in the barrel 14. For gas operated machine guns, such as the
M240 machine gun, the force from this gas is what drives the firing
mechanism 34 back to its original fire ready position.
7. Extraction Action. The extraction action removes the empty case
of the discharged munition 38 from the chamber. After the unlocking
action in the M240 machine gun, the empty case from the discharged
munition 38 is withdrawn from the chamber by an extractor.
8. Ejecting Action. The ejecting action ejects the empty case from
the firearm 10. With regards to the M240 machine gun, an ejector
pushes from the top and the extractor pulls from the bottom to push
the empty case from an ejection port in the firearm 10.
9. Cocking Action. The cocking action completes the return of the
firing mechanism 34 to the fire ready position. In the M240 machine
gun, sufficient gas is made available to the gas cylinder to move
the bolt/operating rod assembly 48 toward the back end 52 of the
receiver assembly 16. This compresses the spring rod 50 until the
firing mechanism 34 is back in the fire ready position and ready to
fire the next munition 38.
A flash event occurs during the munition firing cycle when a flash
of gas propelled by the munition discharge action exits the barrel
14 of the firearm 10. The flash of gas has typically been heated by
the munition discharge action and may be associated with an
electromagnetic discharge that exits the barrel 14 as a result of
the heated gas. The flash event occurs for the M240 machine gun
subsequent to the trigger pull action, the munition stripping
action, the chambering action, the locking action, and the munition
discharge action.
Note that the M240 machine gun provides automatic fire and the
trigger pull action occurs during the initial munition firing
cycle. Subsequent munition firing cycles after the initial firing
cycle do not include a trigger pull action but rather the energy
provided by the discharge of the munition 38 returns the firing
mechanism 34 to the fire ready position, thereby compressing the
spring rod 50. As long as the trigger 20 remains depressed and
there are available unspent munitions 38 in the belt 36, firing
actions 2-9 are repeated during the subsequent munition firing
cycles to automatically fire munitions 38 from the firearm 10.
Thus, the munition stripping action, the chambering action, the
locking action, and the munition discharge action occur prior to
the flash event in subsequent munition firing cycles associated
with the firing of subsequent munitions 38. To stop automatic fire,
the M240 machine gun operator releases the trigger 20 and a trigger
return action places the sear of the bolt/operating rod assembly 48
within the sear notch of the trigger 20. This holds the firing
mechanism 34 in the fire ready position and prevents another
munition firing cycle from taking place. The gun operator may
automatically fire the firearm 10 again. During automatic fire,
another initial munition firing cycle is again followed by
additional subsequent munition firing cycles.
The above-recited firing actions are simply exemplary and the
firing actions implemented by the munition firing cycle of
different types of firearms 10 are dependent on the particular
mechanisms employed by that particular firearm 10. The
above-recited firing actions may or may not be applicable depending
on the type of firearm 10 and the mechanisms employed by the
firearm 10. For example, the munition stripping action described
above is not applicable to firearms 10 fed from clips or magazines
and thus clip or magazine fed firearms 10 may involve different
kinds of firing actions to feed the firearm 10. Also, the locking
action and unlocking action may not be applicable to other firearms
10 depending on the particular firing mechanism 34 being utilized
by the firearm 10. Other firearms 10, such as semi-automatic
firearms 10, may require a trigger pull action for every munition
firing cycle.
Even if one of the above-recited firing actions is applicable to a
particular firearm 10, the firing action may take place in a
different order than the order recited above. For instance, in
forward bolt machine guns, the munition 38 is already in the
chamber when the trigger 20 is pulled and thus the chambering
action may take place after the munition discharge action. In
addition, the implementation of the above-recited firing actions
may be dependent on particular mechanisms utilized by the firearm
10. To demonstrate, in recoil-based machine gun systems, the firing
mechanism 34 is not gas propelled but rather is the result of the
recoil force that pushes the gun backwards. This disclosure is not
limited to any particular type of firearm 10 or set of firing
mechanisms 34 since the laser transmission systems 12 and methods
disclosed herein may be utilized to more accurately reflect
munitions strikes from any type of firearm 10.
Referring now to FIGS. 1 and 3, FIG. 3 illustrates one embodiment
of the laser transmission system 12 mountable on the barrel 14 of
the firearm 10. The laser transmission system 12 in the embodiment
shown in FIG. 3 is for the M240 machine gun. In this particular
embodiment, the laser transmission system 12 has a mounting
apparatus 54 that has been mounted on the laser transmission system
12 so that the orientation of the transmission path 28A is
substantially parallel to the barrel 14. The mounting apparatus 54
in FIG. 3 has a mounting body 56 shaped to receive the barrel 14
and a securement section 58 that attaches underneath the mounting
body 56 through screws or the like to removably secure the laser
transmission system 12 to the firearm 10. Adjustment mechanisms and
the like may be provided to adjust the angle of the laser 26
relative to the barrel 14 if desired.
However, any suitable mechanism may be employed to mount the laser
transmission system 12 to the firearm 10. For example, the laser
transmission system 12 may have a mounting apparatus 54 that allows
for the laser transmission system 12 to be welded or integrated
into the firearm 10. Furthermore, other embodiments of the mounting
apparatus 54 may be utilized to mount the laser transmission system
12 to other parts of the firearm 10, such as the receiver assembly
16.
The laser transmission system 12 has been configured so that the
firearm 10 may be employed in a military combat training system. A
laser 26 is initiated each time a munition 38 is fired from the
firearm 10 to simulate a munition strike. Typically, the munitions
38 fired during battle field training exercises are blank
munitions. Often, discharges from blank munitions do not provide
the necessary forces to complete the munition firing cycle. As a
result, the barrel 14 of the firearm 10 may be fitted with a blank
fire adaptor 60. The blank fire adaptor 60 increases the energy
provided to cycle the firearm 10 by partially blocking an exit end
62 of the barrel 14. In this manner, the M240 machine gun is
configured to automatically fire blank munitions during battle
field training exercises. For gas-operated machine guns, like the
M240 machine gun, the blank fire adaptor 60 causes gas to escape
the exit end 62 of the barrel 14 at a much slower rate. The
obstructed gas increases the pressure within the barrel 14 and
allows the firearm 10 to cycle. Embodiments of the blank fire
adaptor 60 may be provided to allow for gas flow rate adjustments
so that the gun operator can adjust the amount of gas pressure
within the barrel 14. Recoil operated machine guns may also be
adapted for gas-operation and provided with the blank fire adaptor
60. Other embodiments of the blank fire adaptor 60, such as muzzle
boosters, may be provided to add more energy to the recoiling parts
of the firearm 10.
While firearms 10 generally fire blank munitions during battle
field training exercises, embodiments of the laser transmission
system 12 may be configured to operate with other types of
munitions 38. For example, the laser transmission system 12 may be
designed to operate with specialized munitions 38 designed to fire
non lethal projectiles simply to create the necessary forces to
cycle the firearm 10. Furthermore, military combat training systems
may allow for live rounds to be fired in battle field training
exercises under the appropriate safety conditions. Embodiments of
the laser transmission system 12 may be designed to simulate
munition strikes, even when live ammunition is being fired in a
battle field training exercise, because the laser transmission
system 12 and laser receiver system may allow for electronic data
to be recorded.
FIG. 4 illustrates a block diagram of one embodiment of the laser
transmission system 12. The laser transmission system 12 includes a
laser transmitter 64 operable to transmit the laser 26, a sensing
apparatus 66, and a controller 68 operably associated with the
laser transmitter 64 and the sensing apparatus 66. The sensing
apparatus 66 may be any type of sensing apparatus 66 operable to
sense a sequence of real-time mechanical vibrations of the firearm
10. For example, the sensing apparatus 66 may be one or more
piezoelectric sensors or accelerometers. The controller 68 is
configured to detect whether the sequence of real-time mechanical
vibrations sensed by the sensing apparatus 66 are in accordance
with a predetermined characteristic firing signature of the
firearm. The predetermined characteristic firing signature is based
on a sequence of predetermined mechanical vibrations associated
with the firing of a munition from the firearm. If the controller
68 detects that the sequence of real-time mechanical vibrations are
in accordance with the predetermined characteristic firing
signature, it is very likely that the sequence of real-time
mechanical vibrations have been caused by a munition being fired in
real-time by the firearm. Thus, in response to detecting that the
sequence of real-time mechanical vibrations are in accordance with
the predetermined characteristic firing signature, the controller
68 is configured to initiate transmission of the laser 26 from the
laser transmitter 64.
When firing live munitions, the flash event occurs after the bullet
has left the muzzle. Consequently, barrel skew caused by the flash
event does not reflect the accuracy of the bullet. Initiating laser
transmission after the flash event, on the other hand, causes the
laser to be initiated after, or during, barrel skew, thereby
resulting in a laser being transmitted in a direction that differs
from the direction the firearm was aimed at the time the trigger
was pulled.
To more accurately reflect munition strikes from the firearm, the
predetermined characteristic firing signature is based on a
sequence of predetermined mechanical vibrations that occur prior to
the flash event. In particular, the predetermined characteristic
firing signature is based on a sequence of predetermined mechanical
vibrations resulting from at least a first pre-flash firing event
and a subsequent second pre-flash firing event. If the sequence of
real-time mechanical vibrations is detected, or otherwise
determined, to be in accordance with the predetermined
characteristic firing signature the laser is transmitted.
A firing event is a firing action, combination of firing actions,
or other occurrence, that causes detectable or sensible mechanical
vibrations of the firearm during the munitions firing cycle of a
firearm. For example, one example of a firing event is the flash
event that occurs during the munitions firing cycle of the firearm,
as explained above. However, unlike the flash event, a pre-flash
firing event takes place during the munitions firing cycle prior to
the flash event. Since a pre-flash firing action is an occurrence
that takes place prior to the flash event during a munitions firing
cycle and is associated with the firing of a munition from the
firearm, a pre-flash firing action is a type of pre-flash firing
event. For example, the trigger pull action, the munition stripping
action, the chambering action, the locking action, and the munition
discharge action are each pre-flash firing events.
The predetermined characteristic firing signature may be based on
the sequence of predetermined mechanical vibrations from any first
pre-flash firing event and any subsequent second pre-flash firing
event, so long as the predetermined mechanical vibrations of the
first pre-flash firing event and the predetermined mechanical
vibrations of the second pre-flash firing event each define
discrete mechanical impulse responses. For example, the
predetermined characteristic firing signature may be based on the
sequence of predetermined mechanical vibrations resulting from the
trigger pull action and the subsequent chambering action. In
another embodiment, the predetermined characteristic firing
signature may be based on the sequence of predetermined mechanical
vibrations resulting from the trigger pull action and the
subsequent munition discharge action. In yet another embodiment,
the predetermined characteristic firing signature may be based on
the sequence of predetermined mechanical vibrations resulting from
the trigger pull action and the subsequent munition stripping
action.
A pre-flash firing event may also be a combination of pre-flash
firing actions. Thus, the predetermined characteristic firing
signature may be based on the sequence of predetermined mechanical
vibrations resulting from a first pre-flash firing action and a
combination of subsequent pre-flash firing actions so long as the
predetermined mechanical vibrations resulting from the first
pre-flash firing action and the combination of subsequent pre-flash
firing actions define discrete mechanical impulse responses. For
example, the combination of the munition stripping action and the
chambering action may be combined to define a pre-flash firing
event. The predetermined mechanical vibrations resulting from the
combination of the munition stripping action and the chambering
action define a discrete mechanical impulse response relative to
the predetermined mechanical vibrations resulting from the trigger
pull action. Thus, in one embodiment, the predetermined
characteristic firing signature is based on the sequence of
predetermined mechanical vibrations resulting from the trigger pull
action, as the first pre-flash firing event, and the combination of
the munition stripping action and the chambering action, as the
subsequent second pre-flash firing event.
One of the two pre-flash firing events can also be an occurrence
that takes place within a particular firing action prior to the
flash event so long as the predetermined mechanical vibrations
resulting from the pre-flash firing event define a discrete
mechanical impulse response relative to the predetermined
mechanical vibrations resulting from the other of the two pre-flash
firing events. For instance, as discussed above, gases are fed back
from a gas plug regulator in the barrel to a gas cylinder during
the unlocking action of the M240 machine gun. While gases may
continue to flow through the gas plug regulator after the flash
event, the gases are initially received during the unlocking action
by the gas plug regulator prior to the flash event. Thus, the
predetermined characteristic firing signature may be based on the
sequence of predetermined mechanical vibrations resulting from the
chambering action, as the first pre-flash firing event, and the
gases of the firearm initially reaching the gas cylinder, as the
subsequent second pre-flash firing event.
Since the predetermined characteristic firing signature is based on
the predetermined mechanical vibrations of at least a first
pre-flash firing event and a second subsequent pre-flash firing
event, the controller 68 detects that the real-time mechanical
vibrations are in accordance with the predetermined characteristic
firing event signature prior to the flash event. In this manner,
the controller 68 initiates transmission of the laser 26 before the
changes in orientation caused by the flash event. Furthermore, the
controller 68 prevents the gun operator from "cheating", because
the predetermined characteristic firing signature is based on the
predetermined mechanical vibrations resulting from multiple
pre-flash firing events.
In the embodiment illustrated in FIG. 4, the sensing apparatus 66
generates sequences of real-time electronic responses 70 based on
sensed real-time mechanical vibrations. The controller 68 is
coupled to the sensing apparatus 66 and receives the real-time
electronic responses 70 from the sensing apparatus 66. The
controller 68 uses the real-time electronic responses 70 to detect
whether the real-time mechanical vibrations are in accordance with
the predetermined characteristic firing signature of the firearm.
In this embodiment, the controller 68 is configured to generate a
laser initiation signal 71 upon detecting that the sequence of
real-time mechanical vibrations are in accordance with the
predetermined characteristic firing signature. The laser initiation
signal 71 is operable to cause the laser transmitter 64 to initiate
transmission of the laser 26.
The controller 68 may have any type of suitable configuration to
detect that the sequence of real-time mechanical vibrations are in
accordance with the predetermined characteristic firing signature.
As explained in further detail below, the control device(s) used by
the controller 68 may depend on the type of sensing apparatus 66
being utilized to sense the sequence of real-time mechanical
vibrations and the manner in which the controller 68 detects that
the sequence of real-time mechanical vibrations are in accordance
with the predetermined characteristic firing signature of the
firearm.
Referring now to FIGS. 4 and 5, FIG. 5 illustrates one embodiment
of exemplary procedures for designing the controller 68 of the
laser transmission system 12. The embodiment of the exemplary
procedures of FIG. 5 design the controller 68 shown in FIG. 4 to
operate with the M240 machine gun illustrated in FIG. 1. However,
different embodiments of the exemplary procedures of FIG. 5 may be
implemented to design different types of controllers 68. The
controller 68 may be hardware based and/or software based. The
controller 68 may also be designed for a particular firearm,
munition type, sensing apparatus 66, military combat training
system, and/or battle field training exercise.
To begin, a munition is fired from the firearm (procedure 500). The
munition is fired to determine the characteristic firing signature
of the firearm. A sensing apparatus is provided on the firearm to
sense the mechanical vibrations of the firearm that result from
firing the munition. The sensing apparatus used in exemplary
procedure 500 may be the same type of sensing apparatus in the
laser transmission system 12 of FIG. 4, or alternatively, a
different type of sensing apparatus. The sensing apparatus
generates a sequence of electronic responses based on the
mechanical vibrations that result from firing the munition from the
firearm. A characteristic firing signature of the firearm is then
predetermined based on the sequence of mechanical vibrations that
result from a first pre-flash firing event and a second pre-flash
firing event (procedure 502). The controller 68 is then designed to
detect whether a sequence of real-time mechanical vibrations sensed
by the sensing apparatus 66, shown in FIG. 4, is in accordance with
the characteristic firing signature of the firearm and, in
response, cause the laser transmitter 64 to initiate transmission
of the laser 26 (procedure 504).
Referring now to FIGS. 4 and 6, FIG. 6 illustrates one embodiment
of a predetermined characteristic firing signature 72 that was
predetermined in accordance with the exemplary procedure 502 of
FIG. 5 using piezoelectric sensors based on firing the munition
from the firearm in accordance with exemplary procedure 500 of FIG.
5. The predetermined characteristic firing signature 72 is based on
predetermined mechanical vibrations resulting from firing a blank
munition from the M240 machine gun with the blank fire adaptor 60
fitted on the exit end 62 of the barrel 14, as shown in FIG. 3. The
predetermined characteristic firing signature 72 is a sequence of
predetermined electronic responses 73 corresponding to the sequence
of predetermined mechanical vibrations resulting from the pre-flash
firing events of the M240 machine gun during a munitions firing
cycle. A first set 74 of predetermined electronic responses 73
correspond to the sequence of predetermined mechanical vibrations
resulting from the trigger pull action, a second set 76 of
predetermined electronic responses 73 correspond to the sequence of
predetermined mechanical vibrations resulting from the chambering
action, and a third set 78 of the predetermined electronic
responses 73 corresponds to the sequence of predetermined
mechanical vibrations resulting from the munition discharge action.
Thus, the first set 74 of the predetermined electronic responses 73
is a characteristic firing event signature of the trigger pull
action, the second set 76 of the predetermined electronic responses
73 is a characteristic firing event signature of the chambering
action, and the third set 78 of the predetermined electronic
responses 73 is a characteristic firing event signature of the
munition discharge action. The set 80 of electronic responses are
not part of the predetermined characteristic firing signature 72
and are not included within the predetermined electronic responses
73 but rather represent the set 80 of electronic responses that
result from the flash event. Consequently, the first set 74, the
second set 76, and the third set 78 of predetermined electronic
responses 73 each result from predetermined mechanical vibrations
associated with pre-flash firing events, in this case pre-flash
firing actions associated with the firing of the munition from the
firearm.
As mentioned above, the predetermined characteristic firing
signature 72 is based on a sequence of predetermined mechanical
vibrations that result from at least a first pre-flash firing event
and a subsequent second pre-flash firing event. In one embodiment,
to detect that a sequence of real-time mechanical vibrations are in
accordance with the predetermined characteristic firing signature
72 of the firearm, the controller 68 is configured to detect that
the sequence of real-time mechanical vibrations are in accordance
with the first set 74 of predetermined electronic responses 73 and
the second set 76 of predetermined electronic responses 73. In this
manner, the controller 68 is configured to detect that a sequence
of real-time mechanical vibrations result from the trigger pull
action and the chambering action. In response, the controller 68
initiates transmission of the laser 26.
The predetermined characteristic firing signature 72 may be
utilized to determine the real-time pre-flash firing events that
cause initiation of the laser 26 based on any suitable combination
of predetermined pre-flash firing events. For example, in an
alternative embodiment, to detect that a sequence of real-time
mechanical vibrations are in accordance with the predetermined
characteristic firing signature 72 of the firearm, the controller
68 may be configured to detect that the real-time mechanical
vibrations are in accordance with the first set 74 of electronic
responses and the third set 78 of predetermined electronic
responses 73. The controller 68 may thus be configured to detect a
sequence of real-time mechanical vibrations that result from the
trigger pull action and the munition discharge action when a
munition is fired in real-time. In yet another alternative, all
three sets 74, 76, 78 of predetermined electronic responses 73 may
be utilized to detect that the sequence of real-time mechanical
vibrations are in accordance with the predetermined characteristic
firing signature 72.
As shown in FIG. 6, the first set 74, the second set 76, and the
third set 78 of predetermined electronic responses 73 all occur
prior to the set 80 of electronic responses representing the
mechanical vibrations of the flash event. As a result, if the
controller 68 detects that the sequence of real-time mechanical
vibrations is in accordance with the predetermined characteristic
firing signature 72 of the firearm, transmission of the laser 26 is
initiated prior to the flash event.
Embodiments of the controller 68 may be configured to detect that
the real-time electronic vibrations are in accordance with
predetermined characteristic firing signature 72 based on
predetermined mechanical vibrations of other pre-flash firing
events as well. For example, the predetermined characteristic
firing signature 72 may be based on pre-flash firing events such as
the munition stripping action or the locking action. In addition,
predetermined characteristic firing signatures, such as the
predetermined characteristic firing signature 72 in FIG. 6, may be
predetermined for any type of firearm to design the controller 68
to detect the particular mechanical vibrations resulting from
pre-flash firing actions of the particular firearm and initiate
transmission of the laser 26. In this manner, the controller 68 is
configured to detect the firing of munitions by the firearm during
the battle field training exercises so that the laser 26 can be
used to simulate real-time munition strikes from the firearm.
Referring now to FIGS. 4 and 7, FIG. 7 illustrates one embodiment
of the sensing apparatus 66 shown in FIG. 4, which in this example
is a single piezoelectric sensor 82. The piezoelectric sensor 82 is
operable to sense the sequence of real-time mechanical vibrations
on the firearm by generating sequences of real-time electronic
responses 84 that correspond to the sequences of real-time
mechanical vibrations on the firearm. The real-time mechanical
vibrations cause displacements in the piezoelectric sensor 82 and
the piezoelectric sensor 82 generates real-time electronic
responses 84 as a result of the real-time mechanical vibrations. In
this embodiment, the piezoelectric sensor 82 may receive a
sensitivity signal 86 that sets an adjustable minimum vibrational
level that can be sensed by the piezoelectric sensor 82. The
sensitivity signal 86 can be utilized to set the minimum
vibrational level required to generate real-time electronic
responses 84 from the piezoelectric sensor 82. Thus, the real-time
mechanical vibrations need to have a vibrational level at least as
high as the minimum vibrational level for the piezoelectric sensor
82 to generate the real-time electronic responses 84.
FIG. 8 illustrates one embodiment of real-time electronic responses
84 generated by the piezoelectric sensor 82 shown in FIG. 7. The
real-time electronic responses 84 include a first sequence 88
associated with the real-time mechanical vibrations resulting from
the firing of an initial munition from the M240 machine gun and a
second sequence 90 of real-time electronic responses 84. The first
sequence 88 of real-time electronic responses 84 results from an
initial munition firing cycle that includes a trigger pull action.
The second sequence 90 of real-time electronic responses 84 results
from the flash event associated with the firing of the initial
munition and pre-flash firing events associated with the firing of
a subsequent munition after the initial munition firing cycle but
prior to the trigger return action that stops automatic fire. The
munitions may be blank munitions fired from the M240 machine gun
during a battle field training exercise.
Referring now to FIGS. 4 and 9, FIG. 9 illustrates a block diagram
of one embodiment of the controller 68 in the laser transmission
system 12 shown in FIG. 4. The controller 68 includes at least one
microprocessor 92 and one or more memory devices 94 that store
computer executable instructions 96. The microprocessor 92 executes
the computer executable instructions 96 to provide a software
module. Note that the software module may be either mutually
exclusive of other software modules implemented by the
microprocessor 92 or may be integrated or partially integrated
within other software modules. In this embodiment, the controller
68 is implemented using general purpose processing hardware, such
as the microprocessor 92, so that the controller 68 provides the
desired control functions. Alternatively, the controller 68 may be
implemented using hardware components, such as a hardwired circuit
analog that provides the same functionality as the software module
or through a combination hardwired components and software modules.
The microprocessor 92 and memory devices 94 may be communicatively
associated with a communication interface 98 that allows the
controller 68 to receive and transmit signals to the laser
transmitter 64 and the piezoelectric sensor 82 (shown in FIG. 7),
and, if necessary, to other components external to the laser
transmission system 12. The communication interface 98 may include
one or more communication devices and/or translation hardware
operable to format signals in accordance with the requirements of
the microprocessor 92 and output signals in accordance with the
requirements of the laser transmitter 64, piezoelectric sensor 82,
and/or other components external to the laser transmission system
12. To provide power to operate the microprocessor 92, the memory
devices 94, and the communication interface 98, the controller 68
may include a battery 100.
Referring now to FIGS. 4 and 10, FIG. 10 illustrates one embodiment
of exemplary procedures which are implemented by the laser
transmission system 12 shown in FIG. 4 to initiate transmission of
the laser 26. The exemplary procedures may be implemented by the
laser transmission system 12 during a battle field training
exercise so that the laser 26 can simulate real-time munition
strikes from the M240 machine gun. However, other embodiments of
the exemplary procedures may be implemented to simulate real-time
munition strikes from any firearm.
To initiate transmission of the laser 26, the piezoelectric sensor
82 (shown in FIG. 7) senses a sequence of real-time mechanical
vibrations of the firearm (procedure 1000). The controller 68
determines whether the sequence of real-time mechanical vibrations
are the result of the first pre-flash firing event and the second
pre-flash firing event by detecting that the sequence of real-time
mechanical vibrations are in accordance with the predetermined
characteristic firing signature 72 (shown in FIG. 6) of the firearm
(procedure 1002). The controller 68 initiates transmission of the
laser 26 by the laser transmitter 64 in response to detecting that
the sequence of real-time mechanical vibrations are in accordance
with the predetermined characteristic firing signature 72 of the
firearm 10 (procedure 1004).
Referring again to FIGS. 4 and 8, the piezoelectric sensor 82 in
FIG. 7 may sense a sequence of real-time mechanical vibrations in
accordance with exemplary procedure 1000 of FIG. 10. In this
example, the piezoelectric sensor 82 senses a first sequence of
real-time mechanical vibrations by generating the first sequence 88
of real-time electronic responses 84 in FIG. 8. The first sequence
88 of real-time electronic responses 84 correspond to the sequence
of real-time mechanical vibrations resulting from the firing of the
initial munition from the M240 machine gun. The controller 68 may
receive the first sequence 88 of real-time electronic responses 84
from the piezoelectric sensor 82.
Referring again to FIGS. 6 and 9, the controller 68 (shown in FIG.
9) is operable to detect whether the sequence of real-time
mechanical vibrations are in accordance with the predetermined
characteristic firing signature 72 in accordance with exemplary
procedure 1002 of FIG. 10. In one embodiment, the microprocessor 97
may be a digital signal processor that is configured by the
computer executable instructions 96 to compare the first sequence
88 of real-time electronic responses 84 to the predetermined
characteristic firing signature 72. However, this computation may
take up a significant amount of power from the battery 100. Also,
signature calculations may require storing a version of the
predetermined characteristic firing signature 72 and may be rather
sophisticated.
Referring again to FIGS. 6 and 8, software implemented by the
controller 68 (shown in FIG. 9) configures the controller 68 to
detect when a first one 104 (shown in FIG. 8) in the first sequence
88 of the real-time electronic responses 84 is at least as high as
a first minimum amplitude level 106. For example, the first minimum
amplitude level 106 may be or may be related to an amplitude level
108 (shown in FIG. 6) of the first set 74 of predetermined
electronic responses 73 in the predetermined characteristic firing
signature 72. In this manner, the controller 68 detects that the
first sequence 88 of real-time electronic responses 84 have been
provided in accordance with the first set 74 of predetermined
electronic responses 73. As mentioned above, the first set 74 of
predetermined electronic responses 73 is the characteristic firing
event signature of the trigger pull action. In response to
detecting the first one 104 of the first sequence 88 of real-time
electronic responses 84, the controller 68 is configured to detect
when a second one 110 (shown in FIG. 8) of the first sequence 88 of
the real-time electronic responses 84 is at least as high as a
second minimum amplitude level 112. For example, the second minimum
amplitude level 112 may be or be related to an amplitude level 114
(shown in FIG. 6) of the second set 76 of predetermined electronic
responses 73 in the predetermined characteristic firing signature
72. In this manner, the controller 68 detects that the first
sequence 88 of real-time electronic responses 84 have been provided
in accordance with the second set 76 of predetermined electronic
responses 73. As mentioned above, the second set 76 of
predetermined electronic responses 73 is the characteristic firing
event signature of the chambering action. The controller 68 may
also detect that the second one 110 of the real-time electronic
responses 84 occurs within a time period 116 (shown in FIG. 8)
after the first one 104 of the real-time electronic responses 84.
The time period 116 may be based on a temporal distance 118 (shown
in FIG. 6) between the first set 74 of predetermined electronic
responses 73 and the second set 76 of predetermined electronic
responses 73 in the predetermined characteristic firing signature
72.
By detecting that the first one 104 and the second one 110 of the
first sequence 88 are in accordance with the first set 74 and
second set 76 of predetermined electronic responses 73 in the
predetermined characteristic firing signature 72, the controller 68
is ensured that the first sequence 88 of the real-time electronic
responses 84 are the result of the first pre-flash firing event and
the second subsequent pre-flash firing event, in this case the
trigger pull action and the chambering action, rather than some
unrelated action. This embodiment of the controller 68 may thus
detect that the sequence of real-time mechanical vibrations are in
accordance with the predetermined characteristic firing signature
72 without requiring complex signature calculations or storage of a
version of the predetermined characteristic firing signature 72.
The controller 68 also requires less power from the battery 100 to
allow for longer battle field training exercises.
In still another embodiment, in response to detecting the first one
104 (shown in FIG. 8) from the first sequence 88 of real-time
electronic responses 84, the controller 68 is configured to detect
when a third one 120 from the first sequence 88 of real-time
electronic responses 84 is at least as high as a third minimum
amplitude level 122, rather than or in addition to the second one
110 (shown in FIG. 8) of the real-time electronic responses 84. The
third minimum amplitude level 122 may be or be related to an
amplitude level 124 (shown in FIG. 6) of the third set 78 of
predetermined electronic responses 73 in the predetermined
characteristic firing signature 72. In this manner, the controller
68 detects that the first sequence 88 of real-time electronic
responses 84 have been provided in accordance with the third set 78
of predetermined electronic responses 73. As discussed above, the
third set 78 of predetermined electronic responses 73 is the
characteristic firing event signature of the munition discharge
action. The controller 68 may also detect that the third one 120 of
the real-time electronic responses 84 occurs within a time period
126 (shown in FIG. 8) after the first one 104 in the first sequence
88 of the real-time electronic responses 84. The time period 126
may be based on a temporal distance 127 (shown in FIG. 6) between
the first set 74 and the third set 78 of predetermined electronic
responses 73.
Note that the amplitude level 108 in FIG. 6 is lower than both the
amplitude level 114 and the amplitude level 124 in FIG. 6. The
amplitude level 108 is associated with a first vibrational level
because predetermined mechanical vibrations at the first
vibrational level were required to generate the electronic
responses at the amplitude level 108. Similarly the amplitude level
114 and the amplitude level 124 are each associated with a second
vibrational level and a third vibrational level, respectively,
because predetermined mechanical vibrations at the second
vibrational level and the third vibrational level were required to
generate the second set 76 and the third set 78 of predetermined
electronic responses 73 at the amplitude levels 114, 124.
Consequently, the first set 74, the second set 76, and the third
set 78 of predetermined electronic responses 73 are each associated
with the first vibrational level, the second vibrational level, and
the third vibrational level. Again, the first set 74, the second
set 76, and the third set 78 are the characteristic firing event
signatures of the trigger pull action, the chambering action, and
the munition discharge action.
Referring again to FIGS. 6-8, in one embodiment, the first minimum
amplitude level 106 (shown in FIG. 8) is essentially the same as
the amplitude level 108 (shown in FIG. 6), the second minimum
amplitude level 112 (shown in FIG. 8) is essentially the same as
the amplitude level 114 (shown in FIG. 6), and the third minimum
amplitude level 122 (shown in FIG. 8) is essentially the same as
the amplitude level 124 (shown in FIG. 6). To detect that the first
one 104 (shown in FIG. 8) of the first sequence 88 in the real-time
electronic responses 84 is in accordance with the first set 74
(shown in FIG. 6) of predetermined electronic responses 73, the
controller 68 may be configured to adjust the sensitivity signal 86
(shown in FIG. 7) so that the minimum vibrational level is at the
first vibrational level associated with the amplitude level 108
(shown in FIG. 6). Since the first one 104 in the first sequence 88
of the real-time electronic responses 84 is at least as high as the
first minimum amplitude level 106 (shown in FIG. 8), the first one
104 in the first sequence 88 of real-time electronic responses 84
has been caused by a real-time mechanical vibration at least as
high as the first vibrational level.
In response to detecting the first one 104 in the first sequence 88
of the real-time electronic responses 84, the controller 68 adjusts
the sensitivity signal 86 (shown in FIG. 7) to the second
vibrational level associated with the amplitude level 114 (shown in
FIG. 6) or the third vibrational level associated with the
amplitude level 114 (shown in FIG. 6). To detect that the second
one 110 (shown in FIG. 8) of the first sequence 88 in the real-time
electronic responses 84 is in accordance with the second set 76
(shown in FIG. 6) of predetermined electronic responses 73, the
controller 68 adjusts the sensitivity signal 86 (shown in FIG. 7)
so that the minimum vibrational level is at the second vibrational
level associated with the amplitude level 114 (shown in FIG. 6). To
detect that the third one 104 (shown in FIG. 8) of the first
sequence 88 in the real-time electronic responses 84 is in
accordance with the third set 78 (shown in FIG. 6) of predetermined
electronic responses 73, the controller 68 adjusts the sensitivity
signal 86 (shown in FIG. 7) so that the minimum vibrational level
is at the third vibrational level associated with the amplitude
level 124 (shown in FIG. 6).
In another embodiment, rather than providing a single piezoelectric
sensor 82, the sensing apparatus 66 may include more than one
piezoelectric sensor 82 each set to different minimum vibrational
levels. The controller 68 detects each of the first one 104 (shown
in FIG. 8) and the second one 110 (shown in FIG. 8) and the third
one 120 (shown in FIG. 8) in the first sequence 88 of real-time
electronic responses 84 from different piezoelectric sensors in the
sensing apparatus 66 (shown in FIG. 4).
Referring again to FIGS. 4 and 9, the controller 68 illustrated in
FIG. 9 initiates transmission of the laser 26 in accordance with
the exemplary procedure 1004 shown in FIG. 10. In this embodiment,
the controller 68 has been configured to generate and send the
laser initiation signal 71 in response to the controller 68
detecting that the sequence of real-time mechanical vibrations are
in accordance with the predetermined characteristic firing
signature 72 (shown in FIG. 6).
Referring now to FIGS. 4 and 11, FIG. 11 illustrates one embodiment
of a second predetermined characteristic firing signature 128. The
second predetermined characteristic firing signature 128 may be
utilized to again initiate transmission of the laser 26 when a
subsequent munition is fired from the M240 machine gun after
detecting that the initial munition has been fired from the M240
machine gun but prior to the trigger release action. As discussed
above the munition firing cycle associated with the firing of the
initial munition includes a trigger pull action. However, the M240
machine gun provides automatic fire and, as mentioned above, if the
trigger remains depressed, munition firing cycles after the initial
munition firing cycle do not include the trigger pull action.
Generally, for medium and heavy machine guns like the M240 machine
gun, the initial munition fired may be the most accurate munition
strike since it becomes difficult to aim the M240 machine gun due
to the movement resulting from the flash event. Nevertheless, the
second predetermined characteristic firing signature 128 may be
utilized to detect the firing of subsequent munitions during
automatic fire to more accurately simulate munitions strikes in
accordance with subsequent munition firing cycles that do not
include the trigger pull action.
The second predetermined characteristic firing signature 128 shown
in FIG. 11 has also been generated by piezoelectric sensors as a
sequence of predetermined electronic responses 129. The second
predetermined characteristic firing signature 128 is based on a
sequence of predetermined mechanical vibrations that result from
the flash event associated with the firing of the initial munition,
and pre-flash firing events that occur prior to a flash event
associated with the firing of a subsequent munition. A first set
130 of predetermined electronic responses 129 corresponds to
predetermined mechanical vibrations from the flash event of the
initial munition. A second set 132 of the predetermined electronic
responses 129 correspond to the predetermined mechanical vibrations
from a chambering action associated with firing the subsequent
munition. The third set 134 of predetermined electronic responses
in the second predetermined characteristic firing signature 128
corresponds to predetermined mechanical vibrations from a munition
discharge action associated with firing the subsequent
munition.
Referring now to FIGS. 4, 6, 8 and 11, during a battle field
training exercise, the controller 68 may be configured to detect
that the real-time mechanical vibrations on the firearm are
provided in accordance with second predetermined characteristic
firing signature 128 after detecting that the first sequence 88 of
real-time electronic responses 84 have been provided in accordance
to the predetermined characteristic firing signature 72 in FIG. 6.
In this embodiment, the controller 68 receives the second sequence
90 of real-time electronic responses from the piezoelectric sensor
82 and detects that the second sequence 90 of real-time electronic
responses 84 are in accordance with both the first set 130 of
predetermined electronic responses 129 and the second set 132 of
predetermined electronic responses 129 in the second predetermined
characteristic firing signature 128. Alternatively, the controller
68 receives the second sequence 90 of real-time electronic
responses from the piezoelectric sensor 82 and detects that the
second sequence 90 of real-time electronic responses 84 are in
accordance with both the first set 130 of predetermined electronic
responses 129 and the third set 134 of predetermined electronic
responses 129 in the second predetermined characteristic firing
signature 128. In this manner, the controller 68 may detect that
the real-time mechanical vibrations are provided in accordance with
a flash event associated with the firing of a previously fired
munition, such as the flash event of the initial munition, and with
a pre-flash firing event, such as the chambering action or the
munition discharge action that occur prior to the flash event of
the subsequent munition fired by the firearm. In yet another
alternative embodiment, all three sets of electronic responses may
be utilized to detect that the sequence of real-time mechanical
vibrations are in accordance with the second predetermined
characteristic firing signature 128. Each time the controller 68
detects that a sequence of real-time mechanical vibrations are in
accordance with the second predetermined characteristic firing
signature 128, the controller 68 again initiates transmission of
the laser 26 to simulate another munitions strike from the M240
machine gun.
Embodiments of the laser transmission system 12 may be used in
military combat training system to simulate munitions strikes from
any firearm being utilized in a battle field training exercise. One
such military combat training system is MILES. MILES is a military
combat training system that has been developed to allow for a wide
range of military equipment and weapons to be utilized in battle
field training exercises. MILES is flexible in that a wide variety
of military equipment and weapons may be utilized during battle
field training exercises. Thus, MILES allows for battle field
training exercises to be designed specifically to train infantry
using just firearms. On the other hand, MILES also allows for the
simulation of large scale battle operations including a wide
variety of military equipment and weapons, such as firearm, tanks,
artillery, missiles, biological weapons, chemical weapons, and even
nuclear weapons. Weapons strikes are simulated through the use of
the laser 26. Military personnel, vehicles, and/or equipment are
provided with laser receiver systems. These laser receiver systems
may be illuminated by the laser 26 to determine "kills" from the
weapons strikes. Later versions of MILES record "kills" and
location information at centralized computer systems. These
centralized computer systems help determine the performance of
military equipment and personnel by allowing the data generated
during a battle field training exercise to be gathered and stored
for analysis.
To enable the use of such a wide variety of military equipment and
military weapons, MILES provides standards for the transmission of
data. Embodiments of the laser transmission system 12 may be
configured in accordance with the data transmission standards
provided by MILES. In this manner, the laser transmission system 12
may be mounted on firearm so that the firearm can be used in MILES
battle field training exercises. In a current implementation of
MILES, for each munition fired by the firearm, MILES defines a full
set of messages for a munition strike as four (4) kill messages
followed by one hundred twenty (120) near-miss messages. The laser
transmitter 64 may thus be configured to transmit the laser 26 such
that the laser 26 includes kill messages and near-miss messages
formatted in accordance with MILES. The kill messages and near-miss
messages each take approximately 3.7 milliseconds (ms) in the
current implementation of MILES and at least two (2) kill messages
need to be recorded by the laser receiver system to record a
"kill." Thus, a full set of messages requires around 455 ms.
Referring again to FIGS. 4, 6 and 11, FIG. 6 indicates that, for
the M240 machine gun, the temporal distance 118 (shown in FIG. 6)
between the chambering action and the trigger pull action is
approximately 25 ms, while the temporal distance 127 (shown in FIG.
6) between the munition discharge action and the trigger pull
action is approximately 45 ms. A temporal distance 136 (shown in
FIG. 6) between the flash event and the trigger pull action is
approximately 60 ms. As discussed above, to detect that the
sequence of real-time mechanical vibrations are in accordance with
the predetermined characteristic firing signature 72 of the
firearm, the predetermined characteristic firing signature 72 may
be based on the predetermined mechanical vibrations caused by the
trigger pull action and the chambering action, the trigger pull
action and the munition discharge action, or all three pre-flash
firing actions. In each case, the last pre-flash firing event
occurs sufficiently prior to the flash event of the M240 machine
gun such that transmission of the laser 26 is initiated with
sufficient time for the laser transmitter 64 to transmit more than
two kill messages in the laser 26 before the flash event. If the
last pre-flash firing event is the chambering action, there are
still approximately 35 ms until the flash event and thus all four
kill messages may be transmitted before the flash event. On the
other hand, if the last pre-flash firing event is the munition
discharge action there are still 15 ms until the flash event and
thus three kill messages can be transmitted prior to the flash
event. This is sufficient time for enough kill messages to be
transmitted by the laser 26 prior to the changes in orientation
caused by the flash event so that a "kill" can be recorded by a
laser receiver system illuminated by the laser 26. The laser
transmission system 12 (shown in FIG. 4) can thus more accurately
simulate munitions strikes from the firearm based on the aim
provided by the gun operator.
Note that the M240 machine gun is an automatic firearm that has
munition firing cycles that are significantly faster than 455 ms.
The same is true for other types of automatic machine guns. As a
result, during automatic fire the full set of the transmission of
four (4) kill messages and one hundred twenty (120) near-miss
messages may not be transmitted. Rather, sometime at midstream, the
laser transmission system 12 picks up the real-time mechanical
vibrations on the firearm associated with the firing of a
subsequent munition based on the second predetermined
characteristic firing signature 128 in FIG. 11. The laser
transmission system 12 stops transmitting the set of messages for
the initial munition to prevent any inappropriate correlation of
messaging between munition strikes. The laser transmission system
12 then again initiates transmission of the laser 26 beginning with
a new set of messages. Upon detecting that the real-time mechanical
vibrations indicate that yet another subsequent munition has been
fired during automatic fire based on the second predetermined
characteristic firing signature 128 in FIG. 11, the laser
transmission system 12 stops transmitting the set of messages for
the previously fired subsequent munition and again initiates
transmission of the laser 26 beginning with a new set of messages.
While the laser transmission system 12 may not transmit the full
set of messages for each munition strike, sufficient kill messages
are transmitted prior to the flash events of each fired munition to
accurately approximate a munition strike from the firearm.
Next, FIG. 12 illustrates another embodiment of a predetermined
characteristic firing signature 138 for the M240 machine gun. The
predetermined characteristic firing signature 138 is based on the
sequence of predetermined mechanical vibrations resulting from a
first pre-flash firing event and a subsequent second pre-flash
firing event, which are each associated with the firing of a
munition. The predetermined characteristic firing signature 138 in
FIG. 12 was predetermined utilizing one or more accelerometers in
association with the firing of a blank munition from the M240
machine gun. However, accelerometers may be utilized to
predetermine the predetermined characteristic firing signature 138
of any firearm regardless of the type of munition being fired. The
accelerometers generate the predetermined characteristic firing
signature 138 as a sequence of predetermined electronic responses
140. The sequence of predetermined electronic responses 140 include
predetermined electronic responses 140A, 140B, and 140C. Each of
the predetermined electronic responses 140A, 140B, and 140C is
based on predetermined accelerations resulting from a sequence of
predetermined mechanical vibrations along one of three orthogonal
directions. In this particular example, the sequence of
predetermined electronic responses 140 corresponds to the sequence
of accelerations resulting from three pre-flash firing actions. The
first pre-flash firing event is the trigger pull action while the
subsequent second pre-flash firing event is a combination of the
munition stripping action and the chambering action. The subsequent
second pre-flash firing event thus corresponds to the set of
pre-flash firing actions in which the munition is removed from the
belt and placed in the chamber by the bolt.
In this example, the sequence of predetermined accelerations are
measured along a Z-axis directed vertically from the firearm, a
X-axis substantially perpendicular to the Z-axis and being
substantially parallel to the barrel, a Y-axis substantially
perpendicular to the Z-axis and the X-axis. However, while this
configuration of the Z-axis, X-axis, and Y-axis is convenient, the
direction of the Z-axis, X-axis, and Y-axis relative to the firearm
may be arbitrarily selected. Another configuration of the Z-axis,
X-axis, and Y-axis generates a different sequence of electronic
responses along the Z-axis, X-axis, and Y-axis. Nevertheless, the
predetermined mechanical vibrations are the same and the
predetermined accelerations associated with the predetermined
mechanical vibrations are different simply because the directional
components of the accelerations are being measured along a
different configuration of the Z-axis, X-axis, and Y-axis.
FIG. 13 illustrates another embodiment of the sensing apparatus 66
in FIG. 4. In this example, the sensing apparatus 66 is an
accelerometer 141. The accelerometer 141 generates a sequence of
real-time electronic responses 144. The sequence of real-time
electronic responses 144 correspond to a sequence of real-time
accelerations resulting from a sequence of real-time mechanical
vibrations along three orthogonal directions. The accelerometer 141
may be provided in the laser transmission system 12 so that the
Z-axis 142A, X-axis 142B, and Y-axis 142C of the accelerometer 141
are configured in the same manner as the configuration of the
Z-axis, X-axis, and Y-axis used to predetermine the predetermined
characteristic firing signature 138. In alternate embodiments, the
controller 68 may be configured to perform coordinate system
transformations upon receiving the sequence of real-time electronic
responses 144. Also while a single accelerometer 141 illustrated in
FIG. 13 is used as the sensing apparatus 66 (shown in FIG. 4),
alternate embodiments may utilize multiple accelerometers. For
example, the sensing apparatus 66 may include three accelerometers,
each measuring the accelerations along one axis 142A, 142B, and
142C.
FIG. 14 illustrates one embodiment of the sequence of real-time
electronic responses 144. The sequence of real-time electronic
responses 144 have been generated by the accelerometer 141 during a
battle field training exercise. The sequence of real-time
electronic responses 144 include electronic responses 146A, 146B,
146C resulting from accelerations due to a sequence of real-time
mechanical vibrations along the Z-axis 142A, X-axis 142B, and
Y-axis 142C. The sequence of real-time electronic responses 144 of
FIG. 14 result from of a munition, in this case a blank munition,
being fired during a battle field training exercise.
FIG. 15 illustrates another embodiment of the controller 68 shown
in FIG. 4. The controller 68 is configured to receive the sequence
of real-time electronic responses 144 (shown in FIG. 14) and detect
whether the sequence of real-time electronic responses 144 are in
accordance with the predetermined characteristic firing signature
138 (shown in FIG. 12). The controller 68 in FIG. 15 has been
predesigned based on a transfer function H (x.sub.a, y.sub.a,
z.sub.a). The transfer function H (x.sub.a, y.sub.a, z.sub.a) is
operable to detect whether the sequence of real-time electronic
responses 144 (shown in FIG. 14) are provided in accordance with
the predetermined characteristic firing signature 138 (shown in
FIG. 12). A first noise extraction calculation 148 (shown in FIG.
12) may be performed on the sequence of predetermined electronic
responses 140 to predesign the transfer function H (x.sub.a,
y.sub.a, z.sub.a). The transfer function H (x.sub.a, y.sub.a,
z.sub.a) inputs the sequence of real-time electronic responses 144
(shown in FIG. 14), including the real-time electronic responses
144A, 144B, 144C resulting from real-time accelerations along the
Z-axis 142A, X-axis 142B, and Y-axis 142C due to real-time
mechanical vibrations. If the sequence of real-time electronic
responses 144 (shown in FIG. 14) indicates that there are real-time
mechanical vibrations similar to the predetermined mechanical
vibrations represented by the first noise extraction calculation
148 (shown in FIG. 12), the result of the transfer function
(x.sub.a, y.sub.a, z.sub.a) generates an output designed to
initiate transmission of the laser 26. The transfer function H
(x.sub.a, Y.sub.a, z.sub.a) may be modeled through mathematical
computer techniques and the like. An analog circuit 150 is then
designed in accordance with the transfer function H (x.sub.a,
y.sub.a, z.sub.a) and included in the controller 68.
In the embodiment of an analog circuit 150 of FIG. 15, the
controller 68 includes a communication interface 152 so that the
analog circuit 150 may receive the sequence of real-time electronic
responses 144 (shown in FIG. 14). One exemplary embodiment of the
transfer function H (x.sub.a, y.sub.a, z.sub.a) may perform a
second noise extraction calculation 154 (shown in FIG. 14)
utilizing the sequence of real-time electronic responses 144 (shown
in FIG. 14) so that the analog circuit 150 generates a laser
initiation signal 71 when the second noise extraction calculation
154 (shown in FIG. 14) is within a parameter range of the first
noise extraction calculation 148 (shown in FIG. 12). The first
noise extraction calculation 148 (shown in FIG. 12) and the second
noise extraction calculation 154 (shown in FIG. 14) may each be sum
over the difference calculations. However, any suitable noise
extraction calculation may be utilized, if desired. The controller
68 is coupled by the communication interface 152 to the laser
transmitter 64 (shown in FIG. 4). The laser transmitter 64 sends
the laser initiation signal 71 (shown in FIG. 4) to initiate
transmission of the laser 26 (shown in FIG. 4). The analog circuit
150 thus allows the controller 68 to detect that sequences of
real-time mechanical vibrations sensed by the accelerometer 141 are
in accordance with the predetermined characteristic firing
signature 138 (shown in FIG. 12). In this manner, the controller 68
can initiate transmission of the laser 26 so that the laser 26
simulates a munition strike from the firearm during battle field
training exercises. However, since the predetermined characteristic
firing signature 138 (shown in FIG. 12) is based on the mechanical
vibrations of the first pre-flash firing event and the subsequent
second pre-flash firing event, it becomes very difficult for a gun
operator to cause artificial vibrations having a noise extraction
calculation within the parameter range.
As discussed above, the sequence of real-time electronic responses
144 (shown in FIG. 14) result from of a munition, in this case a
blank munition, being fired during a battle field training
exercise. Since the second noise extraction calculation 154 of the
sequence of real-time electronic responses 144 (shown in FIG. 14)
is in accordance with the predetermined characteristic firing
signature 138 (shown in FIG. 12), the analog circuit 150 generates
the laser initiation signal 71 (shown in FIG. 4) to initiate
transmission of the laser 26. The predetermined characteristic
firing signature 138 (shown in FIG. 12) is for the initial munition
fired during automatic fire by the M240 machine gun and thus the
controller 68 has detected that the sequence of real-time
electronic responses 144 (shown in FIG. 14) correspond to an
initial munition being fired by the M240 machine gun during the
battle field training exercise. Another predetermined
characteristic firing signature may be associated with the firing
of subsequent munitions prior to the trigger release action and
based on different munition firing events. The transfer function H
(x.sub.a, y.sub.a, z.sub.a) of the analog circuit may be designed
so that the laser initiation signal 71 is initiated when sequences
of real-time mechanical vibrations are in accordance with both the
predetermined characteristic firing signature 138 (shown in FIG.
12) or the other predetermined characteristic firing signature
associated with the firing of subsequent munitions from the firearm
during automatic fire. Alternatively, another analog circuit in
addition to the analog circuit of FIG. 15 may be provided with a
transfer function H (x.sub.a, y.sub.a, z.sub.a) specifically
predetermined to detect the sequences of the other predetermined
characteristic firing signature associated with the firing of
subsequent munitions.
Those skilled in the art will recognize improvements and
modifications to the preferred embodiments of the present
disclosure. All such improvements and modifications are considered
within the scope of the concepts disclosed herein and the claims
that follow.
* * * * *
References